| The tear film consists of
three layers: a mucin layer,an aqueous layer,and an oil
layer. The innermost(mucin)layer,secreted by the conjunctival goblet cells,promotes adherence of the aqueous compinent to the hudrophobic epithelial surface of the conjunctiva and cornea. The aqueous layer,accounting for 90% of the tear film thickness,is secreted by the main lacrimal gland and the accessory lacrimal glands. The superficial(oily)layer,produced by the meibomian glands, prevents evaporation and abnormal breakup of the tears. A deficiency of any of these three layers can produce a dry eye syndrome. The most common cause of dry eye is aqueous tear deficiency. |
 |
Canaliculitis | Dacrycocystitis | Normal Tear Film | Keratoconjunctivitis Sicca
Eye Lid | Lacrimal System Disorders | Scleral Disease